Bulldozer



March v 18, l 947.

E. A. PoRcH 2,417,520

BULLDOZER v Filed Nov. 3, 1945 2 Sheets-Sheet l Fig. 2

` INVENTOR EDWIN A. PORCH ATTOR N E Y v March 18, 1947.

E. A. PORCH BULLDOZE'R 2 Sheets-Sheet 2 Filed Nov. 3, 1945 INVENTOR. Bow/N A. PORCH NEY ATToR atentec Mar.18, 1947 ,y `OFFICE I BULLDozER y Y Edwin A. Porch, Canon City,`Colo.

This invention relates to improvements in attachments for converting tractors of the crawler type into earth moving machines, such as bulldozers, scrapers and the like.`

Ordinary tractors of the crawler typey "Which are popularly referred `to by their trade name caterpillar are powerful machines and by providing suitable attachments they can be used for many purposes besides that of the primary function of pulling other machines. i

In the building of roads and other construction projects, large amounts of dirt must be moved and for this purpose various attachments to standard tractors have been invented and manufactured.`

It is the object of this invention to produce a simple and substantial attachment for converting a tractor of the type above mentioned, into a bulldozer for use in earthmoving operations.

Another object of the invention is to produce an attachment that shall be exceedingly simple in its construction, very rugged and which can also be applied without in any way altering the construction of the tractor body.

The above andother obiects that may become apparent as the description proceeds are attained by means of aconstruction and an arrangement of parts that will now be described in detail and for this purpose reference will be had to the accompanying drawings in which the attachment has been illustrated in its preferred form, and in which: Y

Figure 1 is a side elevation with parts broken away, showing the attachment in place on a tractor of the crawler type and showing the blade in operative position;

Figure 2 is a view similar to that shown in Figure 1, but shows the blade in inoperative po-v sition;

Figure 3 is a top plan view of the attachment looking through plane 3 3, in Figure 1;

Figure 4 is a fragmentary end elevation looking in the direction of arrows 4 4, in Figure 3;

Figure 5 is a section taken on line 5 5, Figure 1, with parts broken away to better disclose the construction;

Figure 6 is a fragmentary top plan view looking through plane 6 6, in Figure 5, with parts broken away;

Figure 7 is a section taken on line 1 1, Figure 3; and

Figure 8 isa section taken on line 8 8, Figure*1.'

In Figures .1', 2 and 3 ofthe drawing, a well known type of crawler tractor has been indicated 55` Application November 3, 1945, Serial No. 626,549 i 4 claims. (o1. s7-144 by broken lines for the purpose of showing the relationship of the parts of the attachment to the tractor. The attachment to which this invenion relates consists of a frameformed from structural channel iron and comprising twoside members I0 and ma and a transverse member I I.

In the drawing the width df the channels has purposely been exaggerated in order to make the construction clearer. .I I

The sidemembers 'I0 and Illa may be secured to the tractor in any suitable way, as,` for example, by means of brackets I2; or they may be welded t0 the tractor, if desired. The exact manner in which the attachment.` is attached to the tractor has not been shown as thiscan be effected in sev eral specifically different ways. Frame member IIB is provided at its front endwith a pulley I3, inountedfor rotation onanaxle I4 and at its rear end with two or more pulleys I5, mounted for rotation about axles I6. Adjacent the front end of member ,IIJ an opening I1 has been out in the web, in alignment with the transverse member II. Pulleys I8 `and I9 are secured to the web of member II for rotation about vertical pivots 2U. Frame member Illa, at the top in Figure 3, has a pulley 2I mounted for rotation on anaxle 22. Slidable in the channel on the right hand side of the tractor is a pulleyblock 23, to which is pivotally attached two or more pulleys 24. An anchor block 25 is'attached 'to the pulley block for limited rotary movement about pivot 26.- The tractor itself is provided with a winchhaving a drum which has been designated by reference numeral 2l. The mechanism by which the drum is rotated has not been illustrated for the reason just stated, that it is part of the tractor and is merely utilized for operating the attachment Vwhich forms. the subject of this invention. The

tractor is also provided with apulley 28 that is mounted for rotation about a pivot 29. Pulley 28 is so positioned that cable 30, that has one end connected with the winch drum and passes over pulley 28, will be in one of the pulleys I5'in the manner shown most clearly inFigure 4; `After passing about pulley I5, cable 30 passes around one of the pulleys 24, thence rearwardly and about'the other pulley I5,` thence forwardly abouttthe other pulley 24 and has its end anchored to the frame member at points 3|. I

It will now be apparent that a block and tackle arrangement has been formed in which the tension exerted on cable 30 by the winch is multiplied several times. When the cable is wound onto the position to be received onflanges of channel 26 and to the gusset plates Y 31a that, in turn, are secured to the pusher bars.

A cable 38 has its ends connected with the pusher bars near the front ends thereof. In the drawing the ends of the cable have been shown as encircling an anchor pin-39, afterwhich they 4 cable clamped to a stationary anchor positioned where the anchor block has now been shown.

The side beams or channels are preferably provided with removable covers 43 that enclose the cables and the pulleys and protect them from dust and moisture. The upper surface of transverse member I I is also provided with a cover that has been designated by reference numeral 44.

Attention is called to the great simplicity of the present construction and to the fact that the frame itself can be made from standard structural steel welded or otherwise secured to each other and to the tractor. A single winch, operated by the power takeoff of the engine, controls the position of the blade 31. By means of the arrangement of pulleys IS and 24, it is are secured by means of clamps 40. Of course `v` any other way of securing the ends of the cable may be adopted.

In Vthe form illustrated, cable 38 is formed from a single piece. Beginning now at the anchor pin 39 in Figure 1 the cable extends upwardly about pulley 'I3 and thence rearwardly about the cable anchor block which is rockable about pivot 26. It passes from this forwardly, about the pulley I8 near beam Ill, after which it crosses in the transverse channel II to the pulley I9 adjacent beam Ella and from thence it passes about pulley ZI to the anchor pin 39 at the forward end of the other pusher bar. The bight of the cable that encircles the anchor block 25 is adjusted so as to keep the two pusher bars at the same elevation.

It is now apparent that if the winch is operated to turn drum 21 in a direction to wind cable thereon, pulley block 23 will move rearwardly at a slower rate than that at which the cable is moving. The rearward movement of the pulley block will carry with it the anchor block 25, thereby lifting the front end of the pusher bar assembly until the latter may reach the position shown in Figure 2. By reversing the rotation of the winch, the pusher bar and blade will move downwardly, in response to the action of gravity, into the operative position shown in Figure 1. The pulley block is preferably formed from a short piece of channel iron of the pro-per size to slide within the channel in beam I0 and is provided with a cover 4I that may be secured to the anges 42 by some suitable means or may be welded to the flanges. The two pulleys 24 are mounted for rotation about a shaft 24a supported at its ends in suitable openings in cover 4I and in the web of the pulley block in the manner shown in Figure 8. The anchor block 25 may likewise have the ends of its pivot 26 in suitable openings in the web and cover of the pulley block.

It will be observed from Figures 1 and 2 that the anchor block is not a circular pulley and that it is pivoted eccentrically with respect to the arcuate portion thereof. The anchor block extends forwardly some distance from the pivot. If unequal forces are exerted on the cable 28, they will tend to rotate the anchor block and this will force the cable against the inner surface of one flange of the pulley block so as to lock or latch it against further movement. The anchor block permits a Aslight movement of the cable and a slight rotation of the block itself before the clamping action takes place. It would, of course, be possible to omit the anchor block and to anchor the ends of cables 38 separately to the pulley block or to have the bight of the possible to get any reasonable speed reduction or power ratio so that the tension in the cable will be multiplied many times before it reaches the cable 38.

. It is, lof course, understood that the drawings forming part of this invention are not intended for working drawings and although the parts have been shown as nearly as practical in their proper proportion, some of the parts have been shown to a larger scale than the others so as to make the drawing clearer and more readily understandable.

In the form illustrated, the side beams i5 and lila have -been shown as formed from channels, but it is possible to substitute other forms of structural steel, if it should be found desirable to do so. Channel beams are believed, however, to be the best suited for the purpose here under consideration. The pusher bars 32 may be either channels or I-beams whichever may be found to be the most desirable for this use. The multiplication of the force can be increased beyond that shown by adding an additional pulley I5 and an additional pulley 24. The force ratio will, of course, be limited by the length of the beam and the height to which the pusher frame assembly is to be raised but within such limits the force ratio can be varied.

With the construction shown and described, a single pulley block, positioned on one side of the tractor, is sufficient. This construction requires only one cable from the winch. If two pulley blocks were used, one on each side of the tractor, a duplication of parts vwould be required.

In the drawing the hoisting cables have been shown as connected with the ends of the bars. It is to be understood, however, that any other suitable position may be selected, as it is merely necessary for them to be operatively connected for the purpose of raising the pusher bars.

The lifting frame'is connected with the tractor body, whereas the pusher bars are connected to the rear axle at the outside of the tractor treads and therefore they are' spaced further apart than the bars of thelifting frame.

Having described the invention what is claimed as new 1s:

1. A bulldozer attachment for a tractor of the crawler type having a power operated winch at its rear end, comprising, a frame having a beam attached to one side of the tractor, extending the entire length of the tractor body, a lifting frame comprising two pusher bars, one on each side of the tractor, and a rigid beam connecting the front ends of the pusher bar forming a rigid frame structure, the rear ends of the pusher bars being pivoted to the tractor body near its rear end, a pusher blade'connected with the front end of the pusher frame, and means for raising and lowering the front end or the pusher frame, by power derived from the tractor, comprising a pulley block slidably connected with the longitudinally extending beam, means for moving the block rearwardly comprising, a cable having one end connected with the winch and the other operatively connected with the beam and pulley block assembly, a cable having an intermediate part thereof connected with the pulley block and its ends connected with opposite sides of the pusher frame near its front end a guiding means for the last mentioned cable comprising a plurality of pulleys.

2. A bulldozer attachment for a tractor of the crawler type, having a power operated winch at its rear end, comprising, a beam extending the entire length of the tractor, attached to the tractor body, the rear end of the beam having at least one pulley mounted for rotation about a horizontal axis, the front end of the beam having a pulley mounted for rotation about a horizontal axis, a pulley adjacent the inside of the beam, mounted for rotation about a vertical pivot, a pulley block slidably connected with the beam, at least one pulley rotatably connected with the rear end of the pulley block, a cable having one end connected with the winch, said cable pass ing about thepulley at the rear end of the beam and about a pulley on the pulley bloclathe free end of the cable being anchored to the beam adjacent the rear end thereof, a three sided pusher frame comprising two pusher bars connected at their front ends by a rigid member and pivotally connected with the tractor at their rear ends, at a point below the longitudinally extending beam, a pusher blade connected with the front end of the pusher frame; and means for lifting and lowering the iront end of the pusher frame, comprising, a cable having an intermediate portion thereof connected with the pulley block near its front end, one part of the cable passing forn wardly along the beam, over the pulley rotatingr in a vertical plane, the end of said part being connected with the front of the pusher frame, the other part of the cable passing about the pulley that turns about the vertical axis, thence across the front of the tractor, two cooperating pulleys carried by the tractor on the opposite side from the beam, the cable passing over the two last mentioned pulleys, then downwardly and is secured at its end to the front part of the pusher frame, whereby when the winch is operated to move the pulley block rearwardly, the front end of the pusher frame will be raised.

3. A bulldozer attachment for a tractor of the crawler type having a power operated winch at its rear end, comprising, a frame having two beams, one attached to each side of the tractor body, the rear end of the beam on one side having two pulleys mounted for concentric rotation about a horizontal pivot, the front end of each beam having a pulley mounted for rotation about a horizontal pivot, a pulley adjacent the inner surface of each beam, connected with the beams for rotation about Vertical pivots, a rigid compres sion member extending between the beams, a pulley block slidably connected with the rst mentioned beam, two pulleys connected with the pulley block for rotation about a horizontal axis, a cable having one end connected with the winch, passing about the two pulleys at the rear of the beam and about the two pulleys on the pulley block, the other end of the cable being anchored to the bea-m adjacent the rear end thereof, whereby rotation of the winch drum will move the pulley block rearwardly, a pusher frame comprising two pusher bars connect-ed at their iront ends by a rigid member and a pusher blade and piv otally connected with the tractor at their rear ends, positioned beneath the first mentioned frame, a cable connected at an intermediate point with the front end of the pulley block, one part of said cable passing across the front of the tractor about the two pulleys that rotate about vertical axis and about the pulley at the front end of the beam on the opposite side, with its end connected with the corresponding pusher bar, the other part of the cable extending from the pulley block, about the pulley at the front end of the corresponding beam and attached at its end to the front end of the corresponding= pusher bar, whereby when the first mentioned cable is wound about the winch drum, the iront end of the pusher frame will be raised.

4. A bulldozer attachment for a tractor of the crawler type having a power operated winch at its rear end, comprising, a frame having two beams, one attached to each side of the tractor body, the rear end of the beam on one side hay ing at least one pulley mounted for rotation about a horizontal axis, the front end of each beam having a pulley mounted for rotation about a horizontal axis, a frame member interconnecting the beams to the front of the tractor, a pulley connected with each end of the last mentioned frame member for rotation about a vertical pivot, adjacent the inside of each of the rst mentioned beams, a pulley block slidably connected with one of the iirst mentioned beams, at least one pulley rotatably connected with the pulley block, a cable having one end connected with the winch, said cable passing about the pulley at the rear end of the rst mentioned beam and about the pulley on the pulley block, the free end of the cable being anchored to the beam adjacent the rear end thereof, a pusher frame comprising two pusher bars connected at their iront ends by a rigid member and a pusher blade and pivotally v connected with the tractor at their rear ends,

positioned beneath the iirst mentioned frame, and means comprising a lifting cable having an intermediate portion connected with the pulley block near its front end, one part of the cable extending forwardly, thence downwardlyl over the pulley, the end being connected with the corresponding side oi the pusher frame near its iront end, the other part passing in front of the tractor, about the pulleys turning about the veru tical axis, thence downwardly about the pulley turning about the horizontal axis, the end of the cable being connected with the corresponding side of the pusher frame near its front end.

EDWIN A. PORCI-I.

REFERENCES CITED UNITED STATES PATENTS Name Date LeBleu Dec. 26, 1939 Number 

